in the shootout that ensued in watertown, elder brother, tamerlan tsarnaev got out of the car with explosives strapped to his chest, firing at police officers. at least one was hit and badly wounded. tamerlan was killed, with dzhokhar reportedly ramming the car through police to flee. and that's where we are this afternoon. with a 19-year-old suspected terrorist killer on the loose. and a city at a standstill. nbc news' national investigative correspondent michael isikoff joins us now from boston. mike, just start us off with exactly where this manhunt stands at this very moment, because less than about 20 minutes ago, we understood that there were two suspects that the police were seeking. now we understand that's been reduced to just the one. >> reporter: right. just another example of how much misinformation has been in this case from the beginning. a lot of this is coming from police scanners, where police think as some point they have a suspect or person of interest and it turns out to wash out. just like we often get bum tips in the news business that never quite pan out. earlier today,